On 29/12/2009 15:21, assan alhamoud wrote: > Hello All > > I have some questions and I hope to find answers about Load balancing . > > 1- The first question , our DBA says that it not normal and no logic to > have several instances of tomcat server on the same machine with the same > configuration , is this correct ? No. Your DBA is wrong.
> 2- Each tomcat instance here can serve about 125 user , and I have more than > this number on the server I got alot of problems and usually the instance > hang , is there anyway to get better performance from tomcat. That isn't a Tomcat problem, that is an application problem. The solution is to fix/tune your application. > I am using now 3G memory for each instance and 120 for max_pool_size and > 750 maxThread It isn't clear what the 125 users refers to. Is it concurrent requests, is it concurrent sessions, is it concurrent users (assuming 1 concurrent user == more than 1 concurrent request). From these numbers the application seems very resource intensive. It does appear that it would benefit from some tuning. > 3- The most critical issue I had , when one instance hangs , apache hangs > and then all the application hangs because apache keep trying to connect to > the hanged instance , Is there any way to force apache to bypass the hanged > instance. Yes. But since you haven't told us the Tomcat version, httpd version nor how you are connecting httpd to Tomcat we can't tell you how to fix it. > 4- When instance of tomcat hangs , i forced to restart this instance ( > tomcat server ) the problem is GC can not free memory anymore > Is there anyway to solve the problem instead of restarting the server. Yes. Work out if you have a memory leak or need more memory than is available. If it is a memory leak, fix it. If you need more memory either allocate it or tune your app so it uses less. > 5- at last sometimes I found that the same action repeated many times which > means that apache sends the request more than one time to tomcat server > ,could I have control over this behavior. Maybe, maybe not. If this behaviour is initiated by the user agent you need to manage this in your app. It could also be caused by the fail-over mechanism, in which case I refer you to my answer to point 3 above. Mark --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
